CVE-2025-28016 is a reflected Cross-Site Scripting (XSS) vulnerability identified in the PHPGurukul User Registration & Login and User Management System version 3.3, specifically in the edit-profile.php script. The vulnerability arises from insufficient input sanitization or output encoding of user-supplied parameters: fname, lname, and contact. An attacker can craft a malicious URL containing JavaScript code embedded within these parameters. When a victim user clicks the link and the vulnerable page reflects these parameters without proper encoding, the injected script executes in the victim’s browser context. This can lead to session hijacking, credential theft, or redirection to malicious sites. The CVSS 3.1 base score is 4.8 (medium severity), reflecting that the attack vector is network-based (remote), requires low attack complexity, but requires the attacker to have some privileges (PR:H) and user interaction (UI:R). The scope is changed (S:C), indicating that the vulnerability affects resources beyond the vulnerable component. The impact on confidentiality and integrity is low, with no impact on availability. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability is categorized under CWE-79, which is the standard classification for XSS issues. Given the nature of reflected XSS, exploitation requires social engineering to lure users into clicking malicious links. The vulnerability affects a widely used PHP-based user management system, which is often deployed in web applications requiring user registration and profile management.

For European organizations using PHPGurukul User Registration & Login and User Management System v3.3, this vulnerability poses a moderate risk. Attackers can exploit it to execute arbitrary JavaScript in the context of authenticated users, potentially leading to theft of session cookies, user impersonation, or unauthorized actions within the application. This can compromise user data confidentiality and integrity, especially in environments handling sensitive personal or financial information. Although the vulnerability does not directly affect system availability, the resulting data breaches or unauthorized access could lead to regulatory non-compliance under GDPR, reputational damage, and financial penalties. The requirement for user interaction and some level of privilege reduces the likelihood of mass exploitation but targeted phishing campaigns could be effective. Organizations with customer-facing portals or internal user management systems based on this software are particularly at risk. The reflected XSS can also be leveraged as a stepping stone for more complex attacks, such as delivering malware or conducting further social engineering.

To mitigate this vulnerability, organizations should implement strict input validation and output encoding on all user-supplied data, especially the fname, lname, and contact parameters in edit-profile.php. Employ context-aware encoding (e.g., HTML entity encoding) to neutralize script injection attempts. Use security headers like Content Security Policy (CSP) to restrict execution of unauthorized scripts. Since no official patch is available, consider applying temporary fixes such as sanitizing inputs at the application level or disabling the vulnerable functionality if feasible. Conduct code reviews and penetration testing focused on XSS vectors. Educate users about phishing risks to reduce the chance of successful social engineering. Monitor web server logs for suspicious requests containing script payloads. Finally, plan to upgrade to a patched version once available or consider alternative user management solutions with better security track records.